2 * Copyright (c) 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * Modified Sun Mar 12 10:34:34 1995, faith@cs.unc.edu, for Linux
37 * This program is not related to David Wall, whose Stanford Ph.D. thesis
38 * is entitled "Mechanisms for Broadcast and Selective Broadcast".
40 * 1999-02-22 Arkadiusz MiĆkiewicz <misiek@pld.ORG.PL>
41 * - added Native Language Support
45 #include <sys/param.h>
66 #include "pathnames.h"
67 #include "carefulputc.h"
69 #include "fileutils.h"
70 #include "closestream.h"
73 #define WRITE_TIME_OUT 300 /* in seconds */
75 /* Function prototypes */
76 static char *makemsg(char *fname
, char **mvec
, int mvecsz
,
77 size_t *mbufsize
, int print_banner
);
79 static void __attribute__((__noreturn__
)) usage(FILE *out
)
81 fputs(USAGE_HEADER
, out
);
83 _(" %s [options] [<file> | <message>]\n"), program_invocation_short_name
);
85 fputs(USAGE_SEPARATOR
, out
);
86 fputs(_("Write a message to all users.\n"), out
);
88 fputs(USAGE_OPTIONS
, out
);
89 fputs(_(" -n, --nobanner do not print banner, works only for root\n"), out
);
90 fputs(_(" -t, --timeout <timeout> write timeout in seconds\n"), out
);
91 fputs(USAGE_SEPARATOR
, out
);
92 fputs(USAGE_HELP
, out
);
93 fputs(USAGE_VERSION
, out
);
94 fprintf(out
, USAGE_MAN_TAIL("wall(1)"));
96 exit(out
== stderr
? EXIT_FAILURE
: EXIT_SUCCESS
);
99 int main(int argc
, char **argv
)
103 struct utmp
*utmpptr
;
105 char line
[sizeof(utmpptr
->ut_line
) + 1];
106 int print_banner
= TRUE
;
107 char *mbuf
, *fname
= NULL
;
109 unsigned timeout
= WRITE_TIME_OUT
;
113 static const struct option longopts
[] = {
114 { "nobanner", no_argument
, 0, 'n' },
115 { "timeout", required_argument
, 0, 't' },
116 { "version", no_argument
, 0, 'V' },
117 { "help", no_argument
, 0, 'h' },
121 setlocale(LC_ALL
, "");
122 bindtextdomain(PACKAGE
, LOCALEDIR
);
124 atexit(close_stdout
);
126 while ((ch
= getopt_long(argc
, argv
, "nt:Vh", longopts
, NULL
)) != -1) {
130 print_banner
= FALSE
;
132 warnx(_("--nobanner is available only for root"));
135 timeout
= strtou32_or_err(optarg
, _("invalid timeout argument"));
137 errx(EXIT_FAILURE
, _("invalid timeout argument: %s"), optarg
);
140 printf(UTIL_LINUX_VERSION
);
151 if (argc
== 1 && access(argv
[0], F_OK
) == 0)
153 else if (argc
>= 1) {
158 mbuf
= makemsg(fname
, mvec
, mvecsz
, &mbufsize
, print_banner
);
161 iov
.iov_len
= mbufsize
;
162 while((utmpptr
= getutent())) {
163 if (!utmpptr
->ut_user
[0])
166 if (utmpptr
->ut_type
!= USER_PROCESS
)
169 /* Joey Hess reports that use-sessreg in /etc/X11/wdm/
170 produces ut_line entries like :0, and a write
172 if (utmpptr
->ut_line
[0] == ':')
175 xstrncpy(line
, utmpptr
->ut_line
, sizeof(utmpptr
->ut_line
));
176 if ((p
= ttymsg(&iov
, 1, line
, timeout
)) != NULL
)
190 static void buf_enlarge(struct buffer
*bs
, size_t len
)
192 if (bs
->sz
== 0 || len
> bs
->sz
- bs
->used
) {
193 bs
->sz
+= len
< 128 ? 128 : len
;
194 bs
->data
= xrealloc(bs
->data
, bs
->sz
);
198 static void buf_puts(struct buffer
*bs
, const char *s
)
200 size_t len
= strlen(s
);
202 buf_enlarge(bs
, len
+ 1);
203 memcpy(bs
->data
+ bs
->used
, s
, len
+ 1);
207 static void buf_printf(struct buffer
*bs
, const char *fmt
, ...)
213 buf_enlarge(bs
, 0); /* default size */
214 limit
= bs
->sz
- bs
->used
;
217 rc
= vsnprintf(bs
->data
+ bs
->used
, limit
, fmt
, ap
);
220 if (rc
> 0 && (size_t) rc
+ 1 > limit
) { /* not enoght, enlarge */
221 buf_enlarge(bs
, rc
+ 1);
222 limit
= bs
->sz
- bs
->used
;
224 rc
= vsnprintf(bs
->data
+ bs
->used
, limit
, fmt
, ap
);;
232 static void buf_putc_careful(struct buffer
*bs
, int c
)
234 if (isprint(c
) || c
== '\a' || c
== '\t' || c
== '\r' || c
== '\n') {
236 bs
->data
[bs
->used
++] = c
;
237 } else if (!isascii(c
))
238 buf_printf(bs
, "\\%3o", (unsigned char)c
);
240 char tmp
[] = { '^', c
^ 0x40, '\0' };
245 static char *makemsg(char *fname
, char **mvec
, int mvecsz
,
246 size_t *mbufsize
, int print_banner
)
248 struct buffer _bs
= {.used
= 0}, *bs
= &_bs
;
249 register int ch
, cnt
;
253 line_max
= sysconf(_SC_LINE_MAX
);
257 lbuf
= xmalloc(line_max
);
259 if (print_banner
== TRUE
) {
260 char *hostname
= xgethostname();
261 char *whom
, *where
, *date
;
265 if (!(whom
= getlogin()) || !*whom
)
266 whom
= (pw
= getpwuid(getuid())) ? pw
->pw_name
: "???";
269 warn(_("cannot get passwd uid"));
271 where
= ttyname(STDOUT_FILENO
);
274 warn(_("cannot get tty name"));
275 } else if (strncmp(where
, "/dev/", 5) == 0)
279 date
= xstrdup(ctime(&now
));
280 date
[strlen(date
) - 1] = '\0';
283 * all this stuff is to blank out a square for the message;
284 * we wrap message lines at column 79, not 80, because some
285 * terminals wrap after 79, some do not, and we can't tell.
286 * Which means that we may leave a non-blank character
287 * in column 80, but that can't be helped.
289 /* snprintf is not always available, but the sprintf's here
290 will not overflow as long as %d takes at most 100 chars */
291 buf_printf(bs
, "\r%*s\r\n", TERM_WIDTH
, " ");
293 snprintf(lbuf
, line_max
,
294 _("Broadcast message from %s@%s (%s) (%s):"),
295 whom
, hostname
, where
, date
);
296 buf_printf(bs
, "%-*.*s\007\007\r\n", TERM_WIDTH
, TERM_WIDTH
, lbuf
);
300 buf_printf(bs
, "%*s\r\n", TERM_WIDTH
, " ");
304 * Read message from argv[]
308 for (i
= 0; i
< mvecsz
; i
++) {
309 buf_puts(bs
, mvec
[i
]);
313 buf_puts(bs
, "\r\n");
316 * read message from <file>
320 * When we are not root, but suid or sgid, refuse to read files
321 * (e.g. device files) that the user may not have access to.
322 * After all, our invoker can easily do "wall < file"
323 * instead of "wall file".
325 uid_t uid
= getuid();
326 if (uid
&& (uid
!= geteuid() || getgid() != getegid()))
327 errx(EXIT_FAILURE
, _("will not read %s - use stdin."),
330 if (!freopen(fname
, "r", stdin
))
331 err(EXIT_FAILURE
, _("cannot open %s"), fname
);
336 * Read message from stdin.
338 while (fgets(lbuf
, line_max
, stdin
)) {
339 for (cnt
= 0, p
= lbuf
; (ch
= *p
) != '\0'; ++p
, ++cnt
) {
340 if (cnt
== TERM_WIDTH
|| ch
== '\n') {
341 for (; cnt
< TERM_WIDTH
; ++cnt
)
343 buf_puts(bs
, "\r\n");
347 cnt
+= (7 - (cnt
% 8));
349 buf_putc_careful(bs
, ch
);
353 buf_printf(bs
, "%*s\r\n", TERM_WIDTH
, " ");
357 bs
->data
[bs
->used
] = '\0'; /* be paranoid */
358 *mbufsize
= bs
->used
;